Records consist primarily of interoffice correspondence between the Philipsburg office, the St. Louis office, and the sales office in Cincinnati; and general correspondence. Major interoffice correspondents include L.M. Rumsey Jr., John P. Meyer, Leigh Wyman, John R. Lucas, Dan Smith, Charles G. Ewing, and Joseph Yob. Major outside correspondents include vendors of equipment and supplies, purchasers of manganese and silver, and state and federal agencies.

In addition, there are employment records including accident reports (1916-1924) and payrolls (1911-1937); financial records (1912-1935); map indexes; organizational records; production records, consisting of assay reports (1913-1939), manganese and silver shipping notices (1916-1943), and shift bosses' daily reports (1923-1925). Reports include weekly narrative reports on mine operations. There is a subject file on manganese including specifications, lists of purchasers, shipments by state, and a report on Philipsburg manganese. Miscellany includes ads for equipment, a scrapbook re mill construction materials, and field survey books.